Immediately following his ordination as president of the Church, Spencer W. Kimball states that a change in the priesthood restriction could come, but only through revelation.
David Mitchell, "President Spencer W. Kimball Ordained Twelfth President of the Church." Ensign 4, no. 2 (February 1974): 2–7, accessed June 22, 202, p. 6
—Blacks and the priesthood: I am not sure that there will be a change, although there could be. We are under the dictates of our Heavenly Father, and this is not my policy or the Church’s policy. It is the policy of the Lord who has established it, and I know of no change, although we are subject to revelations of the Lord in case he should ever wish to make a change.